<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>
    var socket;
    if (window.WebSocket) {
        socket = new WebSocket("ws://localhost:8888/hello");
        //接受服务器的信息
        socket.onmessage = function (ev) {
            var rt = document.getElementById("responseText")
            rt.value = rt.value + ev.data;
        }
        //连接开启
        socket.onopen = function (ev) {
            var rt = document.getElementById("responseText");
            rt.value = "连接开启了...";
        }
        //连接关闭
        socket.onclose = function (ev) {
            var rt = document.getElementById("responseText");
            rt.value = rt.value + "\n" + "连接关闭了...";
        }
    }else {
        alert("当前浏览器不支持websocket")
    }
    function send(message) {
        if (!window.socket) {
            return;
        }
        if (socket.readyState == WebSocket.OPEN) {
            socket.send(message);
        }else {
            alert("连接未开启...")
        }
    }
</script>
<form action="/hello" method="get" onsubmit="return false">
    <textarea name="message" style="height: 300px; width: 300px;"></textarea>
    <input type="button" value="发送消息" onclick="send(this.form.message.value)"/>
    <textarea id="responseText" style="height: 300px; width: 300px;"></textarea>
    <input type="button" value="清空内容" onclick="document.getElementById('responseText').value = ''"/>
</form>
</body>
</html>